An obligate parasite, or holoparasite, is a parasitic organism that cannot complete its life-cycle without exploiting a suitable host.
Part of the Andes mountain range, Aconcagua is the second highest of the Seven Summits, behind only Mount Everest in Asia. At 22,837 feet (6,961 meters), not only is it the highest mountain in South America, it is the tallest peak in all of the Americas as well as the Southern and Western Hemispheres.
If only mountains in the 48 continental states are counted, Mt. Whitney in California is the tallest US mountain at 4,421 meters (14,505 feet). However, outside of Turkey, Iran and northern Iraq, there are few true mountains in the Middle East, unlike the United States which has numerous mountain ranges.